Confining system for ground-effect machine

ABSTRACT

An arrangement for sustaining and/or guiding a load such as a machine or vehicle over a bearing surface by means of air cushions confined in a chamber formed inside an annular troughshaped inflatable wall between said bearing surface and a movable partition forming with the load and an annular deformable wall a chamber of a variable volume. The input of a compressed fluid into the latter feeds through ports in the partition the cushionconfining chamber so that the latter is sustained at a small self-adjusting distance over the bearing surface.

Unite States Patent Croix-arie et al.

[ Mar. 7, 1972 [54] CONFINING SYSTEM FOR GROUND- EFFECT MACHINE [72]lnventors: Francis Marie Jean Croix-Marie, Viry- Chatillon; RobertGeorges Grignon, Verriere le Buisson, both of France [73] Assignee:Bertin 8: Cie, Plaisir, France [22] Filed: Dec. 29, 1969 21] Appl. No.:888,516

[30] Foreign Application Priority Data Dec. 26, 1968 France ..l80809[52] US. Cl ..180/124, 180/121 [51] Int. Cl .Bv l/06, B60v H16 [58]Field ofSearch ..l/124, 125, 121

[56] References Cited UNITED STATES PATENTS Billman "/124 Mackie 124Guienne.... ..l80/127 X Scheel ....180/124 X Bertin et al. .L ..180/124Primary Examine rA. Harry Levy Attorney-Stevens, Davis, Miller & Mosher[57] ABSTRACT An arrangement for sustaining and/or guiding a load suchas a machine or vehicle over a bearing surface by means of air cushionsconfined in a chamber fonned inside an annular trough-shaped inflatablewall between said bearing surface and a movable partition forming withthe load and an annular deformable wall a chamber of a variable volume.The input of a compressed fluid into the latter feeds through ports inthe partition the cushion-confining chamber so that the latter issustained at a small self-adjusting distance over the bearing surface.

4 Claims, 8 Drawing Figures PAIENIEDMR 71972 3. 647. 018

' I sum 3 or 4 CONFINING SYSTEM FOR GROUND-EFFECT MACHINE Our inventionhas for its object improved means for establishing and maintaining acompressed fluid cushion between a load and a bearing surface over whichsaid load is to move. Said load is preferably carried and/or guided by aplurality of arrangements designed in accordance with our inven tion andfed with compressed fluid through independent means.

Our improved arrangement comprises a frame or plate extending inparallelism with the bearing surface, means for defining together withsaid frame a chamber of a variable volume, inflatable means definingtogether with said bearing surface a cushion-confining chamber, meansconnecting the first-mentioned means with the inflatable means, thevariable volume chamber communicating with the cushion-confiningchamber.

According to a further feature of our invention the means defining thevariable volume chamber may include an endless wall of a generalfrustoconical shape flaring towards the bearing surface.

According to a still further object of our invention, the inflatablemeans defining the cushion-confining chamber include a deformable walladvantageously of an annular shape, facing said bearing surface throughits convexity.

According to yet another feature, the means connecting the meansdefining on the one hand the variable volume chamber and on the otherhand the cushion-confining chamber include a movable partition lying ata variable distance from the frame of the arrangement and extendingbetween said chambers.

Furthermore, the outer edge of the wall incorporated with thecushion-confining means is connected, fluidtightly with reference to theload-sustaining fluid, with said movable partition whereas the inneredge of said wall can be connected with said movable partition by-meanswhich may be fluidtight with reference to said load-sustaining fluid orelse allow said fluid to flow through them. In the former case, ourimproved arrangement includes means through which the variable volumechamber communicates with the space enclosed between thedeformable-confining wall and the movable partition.

The means through which the two chambers communicate may include meansfor producing a substantial lossof head.

The area of the movable partition extending between the inner and outeredges of the confining wall is advantageously equal to or smaller thanthat bounded by said outer edge. For instance, the first-mentioned areamaybe bounded substantially within a circular line or between twoconcentric circular lines.

Our invention will be clearly understood from a reading of the followingdisclosure, reference being made to the accompanying drawings wherein:

FIG. 1 is a cross section of a first embodiment of our invention,

FIG. 2 illustrates a fraction of FIG. 1 when the movable partition hasmoved nearer the frame so that the endless deformable wall has collapsedto a certain extent FIGS. 3 to are cross sections of three furtherembodiments.

FIG. 6 is a diagrammatic view from below ofa machine in corporatingcarrier arrangements in accordance with our invention.

FIG. 7 is a partial cross section along line VII-VII of FIG. 8, of afurther machine incorporating supporting and guiding means in accordancewith our invention.

FIG. 8 is a partial sectional view along line VIlIVIII of FIG. 7.

Turning to FIG. 1, the arrangement includes two chambers vis. asubplenum chamber 8 and a plenum chamber 13 in substantial contactingrelationship The chamber'8 is bounded by an endless deformable wall 4extending in a manner fluidtight with reference to the sustaining fluidbetween a movable partition 6 and a frame or plate 1 parallel with thebearing surface 2 with reference to which a machine forming the load isto move. The endless wall 4 andframe 1 are rigidly secured together bysecuring plates 5 and bolts 5a. Similarly, the connection between saidwall 4 and the movable partition 6 is obtained by securing plates 7 andbolts 10. The chamber 8 is fed with fluid through a deformable channel 9and its transverse extension 11 out ofa supply of compressed fluid whichis not illustrated.

In the example illustrated, the endless wall 4 forms a substantiallyfrustoconical annulus flaring towards the bearing surface 2. The chamber8 enclosed within said wall communicates through gauged ports 12extending through the partition 6 with the chamber 13 adapted to confineinside it the compressed fluid cushion. Said chamber 13 is definedbetween the movable partition 6 and bearing surface 2 by suitableinflatable means. The latter are constituted in the example illustratedby a deformable annular cushion seal 15 including a apex portion theconvexity of which faces the bearing surface 2. The outer and inner baseportions and 15b of said annular cushion seal I5 are fluidtightlyconnected with the movable partition 6 by securing plates such as 16 and17 respectively, the plate 16 being held in position by bolts 10 alsoengaging the securing plates 7 and theplates 17 being held in positionby bolts 17a. The movable partition 6 and cushion seal 15 enclose thusan annular space 18 communicating with the chamber 8 through ports suchas 19 through which the fluid may pass from the chamber 8 into the space18.

In said embodiment the arrangement disclosed is associated with ahoisting apparatus, the vertical expansion of which is produced by thecompressed fluid. The hoisting apparatus includes a plate 21 carried bythe cooperating surface of the plate 1 and to which is secured adeformable wall 22 enclosing an annular chamber 23 connected through achannel 24 with a supply of compressed fluid which is not illustratedand which is possibly the same as the supply feeding compressed fluidinto the chamber 8. The plate 21 and frame or plate I are interconnectedby linkages constituted by pivotally intercom nected levers 30a and 30bthe outer ends of which are pivotally connected respectively at 20 and25 with said plates 21 and l, the axis connecting the levers of eachlinkage being constituted by a pivot 26. The plate 21 carries in itsturn the frame 27 of the machine or vehicle to be hoisted.

The chamber 8 inside which a pressure pl prevails is fed with compressedfluid through the channels 9 and II and said chamber 8 feeds thefluid-confining chamber 13 through the gauged ports 12. By reason of theloss of head provided by the ports 12 and of the leak of fluid throughthe gap or daylight clearance between the bearing surface 2 and the apexportion of the cushion seal 15, the pressure p2 prevailing in thechamber 13 is lower than the pressure pl within the chamber 8. Thepressure in the annular space 18 is substantially equal to the pressurewithin the chamber-8 since the ports I) allow a free flow of fluidbetween 8 and 18.

During normal operation, the force urging the movable partition 6towards the frame 1 and which is produced by the component of the forcesexerted on the endless wall 4 in a direction substantially perpendicularto said frame I is balanced by the force produced by the difference inpressure between the chambers =8 and 13. If :the daylight clearancedecreases in size, the leakage of the fluid forming the cushion in thechamberl3 decreases also, .which resultsin an increase in the pressuresp2 and pl and a reduction in the losses of head produced through theports 12 between the chambers 8 and '13. The difference between thepressures pl and p2 is thus reduced and the stressing of the endlesswall 4 is no longer balanced, .which leads to a movement of the movablepartition 6 towards the frame I and consequently to an increase in thedaylight clearance. This has .now for its result a return of the leakageof fluid out of the. cushion in the chamber 13 to a value approximatingits original value, whereby the increase in pressure associated with thereduction in the leak output is limited together with the sustainingforce. The movement of the movable partition 6 has for its furtherresult a reduction in the volume of the chamber 28 and finally a dampingof the movement of the movable partition 6 ascribable to a degradationof the energy by reason of the losses of head in the ports I2.

On the other hand when the load of the machine increases, the leak outof the cushion is reduced, which leads to a reduction in the losses ofhead in the ports 12 between the chambers 8 and 13 together with anincrease in the pressure in the chamber 13. The pressure in the chamber8 decreases similarly but to an extent however less than that arising inthe chamber 13 and is compensated by an increase in the area along whichthe endless wall 4 engages the frame 1, which limits the increase inpressure required for balancing the increasing load.

FIG. 2 shows the collapsed position assumed by the endless wall 4 whenthe spacing between the movable partition 6 and frame or plate Idecreases,

In the embodiment illustrated in FIG. 1, the surface extending betweenthe outer and inner edges 15a and 15b of the seal 15 defines asubstantially circular annulus while the chamber 13 within the latter isfed by ports 12 of a gauged cross section located within the circledefined by the inner edge 15b of the confining wall 15. However if as inthe case illustrated in FIG. 3, the area of the circle defined by theinner edge of the confining wall is too small or else if, as illustratedin FIGS. 4 and 5, the inner edge of the cushion-confining wall isreduced to a punctual area, the cushion is fed with compressed fluidthrough ports 32 formed in the inner section of the cushionconfiningwall 29.

As illustrated in FIGS. 3, 4 and S, the wall 29 defines together withthe movable partition 6 an annular space 31 communicating with thechamber 8 through'the agency of ports 33. of a gauged cross sectionextending through the movable partition 6. Said ports produce a loss ofhead which leads during normal operation to a difference in pressurebetween the variable volume chamber 8 and an annular space 31. The totalcrosssectional area of the ports 32 is larger than the totalcross-sectional area of the ports 33.

The inner edge of the cushion-confining wall 29 is secured asillustrated in FIG. 3 by a member 34 and auxiliary means which are notillustrated. As in the case of the embodiment illustrated in FIGS. 4 and5, the wall 29 may be secured through its center to the movablepartition 6 through the agency of a cable, a threaded stud or the likemeans 35.

As illustrated in FIGS. 3 and 4, the cushion-confining wall 29 isconstituted by a plurality of interconnected sections, to wit: asubstantially frustoconical outer section 29a connected with the movablepartition 6 and flaring towards said partition and another substantiallyfrustoconical inner section 291; (FIG. 3), or substantially conicalinner section in the case illustrated in FIG. 4, said section 29!) beingconnected with the movable partition 6 and flaring towards the bearingsurface 2 while a medial downwardly convex section 290 fluidtightly interconnects the two sections 29a and 29b.

The cushion-confining wall 29 of the embodiment illustrated in FIG.includes an outer incurved section merging into a substantially conicalsection flaring towards the bearing surface 2 and the apex of which isconnected axially with the movable partition 6 by means 35 as disclosedwith reference to FIG. 4.

As apparent from inspection of the accompanying drawings the areabounded on the plate 1 within the endless wall 4 is smaller than thearea subjected to a reaction and bounded substantially by the projectionon the bearing surface 2 of a line constituted by the points of the apexportion of the cushion seal which are nearest said bearing surface.

Preferably and as illustrated in FIG. 6, the machine 27 forming the loadis carried by a plurality of supporting arrangements executed inaccordance with our invention as illustrated in FIG. 6 at 39a, 39b, 39c,39d, and which are fed independently of one another by means which arenot illustrated.

The machine 41 illustrated partly in FIGS. 7 and 8 is carried and guidedby arrangements according to our invention. said machine bein sustainedb the sup ortin sections 420 of a track 42 andaeing guide longitudinallyy the medial upwardly directed web 42b forming part of said track withthe interposition between the machine and track. of fluid cushions asillustrated respectively at 43 and 44. These different cushions areproduced and maintained in arrangements according to our invention suchas those disclosed with reference to FIGS. 1 and 2. Said arrangementsare advantageously fed through channels 11 independently of one anotherout of supplies of compressed fluid which are not illustrated.

What we claim is:

l. A surface effect machine movable along a bearing sur face with theinterposition of a pressure fluid cushion formed against said surface,comprising:

a frame structure spaced from said surface and extending generallyparallel thereto,

an endless wall of deformable fluidtight material having a flat smallerend edge extending generally parallel to said structure and sealedthereto and a larger end edge remote therefrom, said wall boundinglaterally a subplenum chamber which is bounded endwise by said structureand which tapers from said larger end edge towards said smaller endedge,

a partition fluidtightly secured to said larger end edge and extendingintermediate said structure and said surface to bound endwise saidsubplenum chamber opposite to said structure, said partition beingdisplaceable relatively to said structure as said endless wall deforms,

a bulging cushion seal having an inner base portion and an outer baseportion both secured to said partition, and a free intermediate apexportion adjacent to said surface, the area defined by said inner baseportion being less than the area defined by said smaller end edge ofsaid endless wall and said latter area being itself less than the areadefined by said apex portion, said cushion seal bounding laterally aplenum chamber which is bounded endwise by said partition and by saidsurface and which presents a daylight clearance defined by said apexportion and said surface,

means for supplying pressure fluid to said subplenum chamber, and

passage means interconnecting said subplenum chamber and said plenumchamber.

2. Surface effect machine as claimed in claim I, wherein said areadefined by said apex portion is itself less than the area defined bysaid outer base portion of said cushion seal.

3. Surface effect machine as claimed in claim 2, wherein said larger endedge of said endless wall is flat and extends generally parallel to saidpartition.

4. Surface effect machine as claimed in claim 2, wherein both said innerand outer base portions of said cushion seal are flat and extendgenerally parallel to said partition.

1. A surface effect machine movable along a bearing surface with theinterposition of a pressure fluid cushion formed against said surface,comprising: a frame structure spaced from said surface and extendinggenerally parallel thereto, an endless wall of deformable fluidtightmaterial having a flat smaller end edge extending generally parallel tosaid structure and sealed thereto and a larger end edge remotetherefrom, said wall bounding laterally a subplenum chamber which isbounded endwise by said structure and which tapers from said larger endedge towards said smaller end edge, a partition fluidtightly secured tosaid larger end edge and extending intermediate said structure and saidsurface to bound endwise said subplenum chamber opposite to saidstructure, said partition being displaceable relatively to saidstructure as said endless wall deforms, a bulging cushion seal having aninner base portion and an outer base portion both secured to saidpartition, and a free intermediate apex portion adjacent to saidsurface, the area defined by said inner base portion being less than thearea defined by said smaller end edge of said endless wall and saidlatter area being itself less than the area defined by said apexportion, said cushion seal bounding laterally a plenum chamber which isbounded endwise by said partition and by said surface and which presentsa daylight clearance defined by said apex portion and said surface,means for supplying pressure fluid to said subplenum chamber, andpassage means interconnecting said subplenum chamber and said plenumchamber.
 2. Surface effect machine as claimed in claim 1, wherein saidarea defined by said apex portion is itself less than the area definedby said outer base portion of saiD cushion seal.
 3. Surface effectmachine as claimed in claim 2, wherein said larger end edge of saidendless wall is flat and extends generally parallel to said partition.4. Surface effect machine as claimed in claim 2, wherein both said innerand outer base portions of said cushion seal are flat and extendgenerally parallel to said partition.